1. Field of the Invention
The present invention relates to an improved inner structure of a power plug.
2. Prior Art
A conventional power plug is shown in FIG. 6. Such plug includes an inner plug core 6 formed with an upper arched concave surface 61. Projection 62 is disposed on the arched concave surface 61. The projection 62 is received within a hole 31 formed at a rear end of a circular grounding terminal 3. On each lateral side of the inner plug core 6 are disposed projections 63 which are received within respective recesses 41, 51 formed at rear ends of positive and negative terminals 4 and 5.
The inner plug core 6 secures the grounding terminal 3 and positive and negative terminals 4 and 5 in position when the inner plug core 6 is inserted in a protective cover 7. The protective cover 7 encloses the grounding terminal 3 and positive and negative terminals 4 and 5. Two channels 64 are formed on a bottom surface of the inner plug core 6 for respective receipt of two inner flanges 71 of the protective cover 7 to couple the protective cover 7 in overlaying relationship with the inner plug core 6. The inner plug core 6 and its associated protective cover 7 are shown in FIG. 7. Such is wrapped by a plastic material and formed into the generally used triple-pole power plug, like that shown in FIG. 5.
It is known from the structure of the above inner plug core that manufacturing of the power plug is costly in both time and labor. In addition, the requirement for the protective cover 7 increases the manufacturing cost and reduces production efficiency.